Emergency doors as used in connection with commercial aircraft are movable between a closed or locked state and an opened state. Upon opening, the emergency door is typically moved outside the aircraft and away from the door opening but is still attached. Upon opening of the emergency door, an inflatable slide is deployed to enable passengers to leave the aircraft.
Actuators often used in connection with the opening of the emergency doors include a spring means to open the door from a closed to an opened position and a piston assembly having a piston rod and at least one piston head that is configured to move within a sealed cylinder containing a hydraulic fluid. The piston head includes at least one orifice that permits fluidic flow between defined chambers to produce a resisting force to control the opening rate of the door. A shock absorbing end stop is also incorporated to prevent a high load on the door assembly when the door reaches its fully open position.